204135 has 16 divisors (see below), whose sum is σ = 337920. Its totient is φ = 105120.

The previous prime is 204133. The next prime is 204137. The reversal of 204135 is 531402.

It is an interprime number because it is at equal distance from previous prime (204133) and next prime (204137).

It is not a de Polignac number, because 204135 - 2¹ = 204133 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

204135 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 246 + ... + 684.

It is an arithmetic number, because the mean of its divisors is an integer number (21120).

2²⁰⁴¹³⁵ is an apocalyptic number.

204135 is a deficient number, since it is larger than the sum of its proper divisors (133785).

204135 is a wasteful number, since it uses less digits than its factorization.

204135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 478.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 204135 is about 451.8130144208. The cubic root of 204135 is about 58.8806358172.

Adding to 204135 its reverse (531402), we get a palindrome (735537).

The spelling of 204135 in words is "two hundred four thousand, one hundred thirty-five".